Re: crash by cdc_acm driver in kernels 4.8-rc1/5

From: Wim Osterholt
Date: Thu Sep 22 2016 - 15:21:44 EST


On Thu, Sep 22, 2016 at 04:40:50PM +0200, Oliver Neukum wrote:
> OK. Strange. Please do
>
> dmesg -c
> echo 9 > /proc/sysrq-trigger
> modprobe cdc_acm
> echo "module cdc_acm +mpf" > /sys/kernel/debug/dynamic_debug/control
>
> [plug your device in]
>
> and provide the full output of dmesg after that.

On kernel-4.7.4 this gives this little output:

[ 135.279989] sysrq: SysRq : Changing Loglevel
[ 135.280489] sysrq: Loglevel set to 9
[ 146.712004] usbcore: registered new interface driver cdc_acm
[ 146.712537] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 173.257346] usb 6-1: new full-speed USB device number 2 using uhci_hcd
[ 173.450326] usb 6-1: New USB device found, idVendor=0572, idProduct=1340
[ 173.450879] usb 6-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 173.451374] usb 6-1: Product: USB Modem
[ 173.451867] usb 6-1: Manufacturer: Conexant
[ 173.452360] usb 6-1: SerialNumber: 12345678
[ 173.455415] cdc_acm:acm_probe: cdc_acm 6-1:1.0: interfaces are valid
[ 173.455995] cdc_acm 6-1:1.0: ttyACM0: USB ACM device
[ 173.562316] cdc_acm:acm_ctrl_msg: cdc_acm 6-1:1.0: acm_ctrl_msg - rq 0x20, val 0x0, len 0x7, result 7


4.8-rc7 is compiling now..


Regards, Wim.